1.explicit
2.text
3.ident	"ia64.S, Version 2.1"
4.ident	"IA-64 ISA artwork by Andy Polyakov <appro@fy.chalmers.se>"
5
6//
7// ====================================================================
8// Written by Andy Polyakov <appro@fy.chalmers.se> for the OpenSSL
9// project.
10//
11// Rights for redistribution and usage in source and binary forms are
12// granted according to the OpenSSL license. Warranty of any kind is
13// disclaimed.
14// ====================================================================
15//
16// Version 2.x is Itanium2 re-tune. Few words about how Itanum2 is
17// different from Itanium to this module viewpoint. Most notably, is it
18// "wider" than Itanium? Can you experience loop scalability as
19// discussed in commentary sections? Not really:-( Itanium2 has 6
20// integer ALU ports, i.e. it's 2 ports wider, but it's not enough to
21// spin twice as fast, as I need 8 IALU ports. Amount of floating point
22// ports is the same, i.e. 2, while I need 4. In other words, to this
23// module Itanium2 remains effectively as "wide" as Itanium. Yet it's
24// essentially different in respect to this module, and a re-tune was
25// required. Well, because some intruction latencies has changed. Most
26// noticeably those intensively used:
27//
28//			Itanium	Itanium2
29//	ldf8		9	6		L2 hit
30//	ld8		2	1		L1 hit
31//	getf		2	5
32//	xma[->getf]	7[+1]	4[+0]
33//	add[->st8]	1[+1]	1[+0]
34//
35// What does it mean? You might ratiocinate that the original code
36// should run just faster... Because sum of latencies is smaller...
37// Wrong! Note that getf latency increased. This means that if a loop is
38// scheduled for lower latency (as they were), then it will suffer from
39// stall condition and the code will therefore turn anti-scalable, e.g.
40// original bn_mul_words spun at 5*n or 2.5 times slower than expected
41// on Itanium2! What to do? Reschedule loops for Itanium2? But then
42// Itanium would exhibit anti-scalability. So I've chosen to reschedule
43// for worst latency for every instruction aiming for best *all-round*
44// performance.
45
46// Q.	How much faster does it get?
47// A.	Here is the output from 'openssl speed rsa dsa' for vanilla
48//	0.9.6a compiled with gcc version 2.96 20000731 (Red Hat
49//	Linux 7.1 2.96-81):
50//
51//	                  sign    verify    sign/s verify/s
52//	rsa  512 bits   0.0036s   0.0003s    275.3   2999.2
53//	rsa 1024 bits   0.0203s   0.0011s     49.3    894.1
54//	rsa 2048 bits   0.1331s   0.0040s      7.5    250.9
55//	rsa 4096 bits   0.9270s   0.0147s      1.1     68.1
56//	                  sign    verify    sign/s verify/s
57//	dsa  512 bits   0.0035s   0.0043s    288.3    234.8
58//	dsa 1024 bits   0.0111s   0.0135s     90.0     74.2
59//
60//	And here is similar output but for this assembler
61//	implementation:-)
62//
63//	                  sign    verify    sign/s verify/s
64//	rsa  512 bits   0.0021s   0.0001s    549.4   9638.5
65//	rsa 1024 bits   0.0055s   0.0002s    183.8   4481.1
66//	rsa 2048 bits   0.0244s   0.0006s     41.4   1726.3
67//	rsa 4096 bits   0.1295s   0.0018s      7.7    561.5
68//	                  sign    verify    sign/s verify/s
69//	dsa  512 bits   0.0012s   0.0013s    891.9    756.6
70//	dsa 1024 bits   0.0023s   0.0028s    440.4    376.2
71//
72//	Yes, you may argue that it's not fair comparison as it's
73//	possible to craft the C implementation with BN_UMULT_HIGH
74//	inline assembler macro. But of course! Here is the output
75//	with the macro:
76//
77//	                  sign    verify    sign/s verify/s
78//	rsa  512 bits   0.0020s   0.0002s    495.0   6561.0
79//	rsa 1024 bits   0.0086s   0.0004s    116.2   2235.7
80//	rsa 2048 bits   0.0519s   0.0015s     19.3    667.3
81//	rsa 4096 bits   0.3464s   0.0053s      2.9    187.7
82//	                  sign    verify    sign/s verify/s
83//	dsa  512 bits   0.0016s   0.0020s    613.1    510.5
84//	dsa 1024 bits   0.0045s   0.0054s    221.0    183.9
85//
86//	My code is still way faster, huh:-) And I believe that even
87//	higher performance can be achieved. Note that as keys get
88//	longer, performance gain is larger. Why? According to the
89//	profiler there is another player in the field, namely
90//	BN_from_montgomery consuming larger and larger portion of CPU
91//	time as keysize decreases. I therefore consider putting effort
92//	to assembler implementation of the following routine:
93//
94//	void bn_mul_add_mont (BN_ULONG *rp,BN_ULONG *np,int nl,BN_ULONG n0)
95//	{
96//	int      i,j;
97//	BN_ULONG v;
98//
99//	for (i=0; i<nl; i++)
100//		{
101//		v=bn_mul_add_words(rp,np,nl,(rp[0]*n0)&BN_MASK2);
102//		nrp++;
103//		rp++;
104//		if (((nrp[-1]+=v)&BN_MASK2) < v)
105//			for (j=0; ((++nrp[j])&BN_MASK2) == 0; j++) ;
106//		}
107//	}
108//
109//	It might as well be beneficial to implement even combaX
110//	variants, as it appears as it can literally unleash the
111//	performance (see comment section to bn_mul_comba8 below).
112//
113//	And finally for your reference the output for 0.9.6a compiled
114//	with SGIcc version 0.01.0-12 (keep in mind that for the moment
115//	of this writing it's not possible to convince SGIcc to use
116//	BN_UMULT_HIGH inline assembler macro, yet the code is fast,
117//	i.e. for a compiler generated one:-):
118//
119//	                  sign    verify    sign/s verify/s
120//	rsa  512 bits   0.0022s   0.0002s    452.7   5894.3
121//	rsa 1024 bits   0.0097s   0.0005s    102.7   2002.9
122//	rsa 2048 bits   0.0578s   0.0017s     17.3    600.2
123//	rsa 4096 bits   0.3838s   0.0061s      2.6    164.5
124//	                  sign    verify    sign/s verify/s
125//	dsa  512 bits   0.0018s   0.0022s    547.3    459.6
126//	dsa 1024 bits   0.0051s   0.0062s    196.6    161.3
127//
128//	Oh! Benchmarks were performed on 733MHz Lion-class Itanium
129//	system running Redhat Linux 7.1 (very special thanks to Ray
130//	McCaffity of Williams Communications for providing an account).
131//
132// Q.	What's the heck with 'rum 1<<5' at the end of every function?
133// A.	Well, by clearing the "upper FP registers written" bit of the
134//	User Mask I want to excuse the kernel from preserving upper
135//	(f32-f128) FP register bank over process context switch, thus
136//	minimizing bus bandwidth consumption during the switch (i.e.
137//	after PKI opration completes and the program is off doing
138//	something else like bulk symmetric encryption). Having said
139//	this, I also want to point out that it might be good idea
140//	to compile the whole toolkit (as well as majority of the
141//	programs for that matter) with -mfixed-range=f32-f127 command
142//	line option. No, it doesn't prevent the compiler from writing
143//	to upper bank, but at least discourages to do so. If you don't
144//	like the idea you have the option to compile the module with
145//	-Drum=nop.m in command line.
146//
147
148#if defined(_HPUX_SOURCE) && !defined(_LP64)
149#define	ADDP	addp4
150#else
151#define	ADDP	add
152#endif
153
154#if 1
155//
156// bn_[add|sub]_words routines.
157//
158// Loops are spinning in 2*(n+5) ticks on Itanuim (provided that the
159// data reside in L1 cache, i.e. 2 ticks away). It's possible to
160// compress the epilogue and get down to 2*n+6, but at the cost of
161// scalability (the neat feature of this implementation is that it
162// shall automagically spin in n+5 on "wider" IA-64 implementations:-)
163// I consider that the epilogue is short enough as it is to trade tiny
164// performance loss on Itanium for scalability.
165//
166// BN_ULONG bn_add_words(BN_ULONG *rp, BN_ULONG *ap, BN_ULONG *bp,int num)
167//
168.global	bn_add_words#
169.proc	bn_add_words#
170.align	64
171.skip	32	// makes the loop body aligned at 64-byte boundary
172bn_add_words:
173	.prologue
174	.save	ar.pfs,r2
175{ .mii;	alloc		r2=ar.pfs,4,12,0,16
176	cmp4.le		p6,p0=r35,r0	};;
177{ .mfb;	mov		r8=r0			// return value
178(p6)	br.ret.spnt.many	b0	};;
179
180{ .mib;	sub		r10=r35,r0,1
181	.save	ar.lc,r3
182	mov		r3=ar.lc
183	brp.loop.imp	.L_bn_add_words_ctop,.L_bn_add_words_cend-16
184					}
185{ .mib;	ADDP		r14=0,r32		// rp
186	.save	pr,r9
187	mov		r9=pr		};;
188	.body
189{ .mii;	ADDP		r15=0,r33		// ap
190	mov		ar.lc=r10
191	mov		ar.ec=6		}
192{ .mib;	ADDP		r16=0,r34		// bp
193	mov		pr.rot=1<<16	};;
194
195.L_bn_add_words_ctop:
196{ .mii;	(p16)	ld8		r32=[r16],8	  // b=*(bp++)
197	(p18)	add		r39=r37,r34
198	(p19)	cmp.ltu.unc	p56,p0=r40,r38	}
199{ .mfb;	(p0)	nop.m		0x0
200	(p0)	nop.f		0x0
201	(p0)	nop.b		0x0		}
202{ .mii;	(p16)	ld8		r35=[r15],8	  // a=*(ap++)
203	(p58)	cmp.eq.or	p57,p0=-1,r41	  // (p20)
204	(p58)	add		r41=1,r41	} // (p20)
205{ .mfb;	(p21)	st8		[r14]=r42,8	  // *(rp++)=r
206	(p0)	nop.f		0x0
207	br.ctop.sptk	.L_bn_add_words_ctop	};;
208.L_bn_add_words_cend:
209
210{ .mii;
211(p59)	add		r8=1,r8		// return value
212	mov		pr=r9,0x1ffff
213	mov		ar.lc=r3	}
214{ .mbb;	nop.b		0x0
215	br.ret.sptk.many	b0	};;
216.endp	bn_add_words#
217
218//
219// BN_ULONG bn_sub_words(BN_ULONG *rp, BN_ULONG *ap, BN_ULONG *bp,int num)
220//
221.global	bn_sub_words#
222.proc	bn_sub_words#
223.align	64
224.skip	32	// makes the loop body aligned at 64-byte boundary
225bn_sub_words:
226	.prologue
227	.save	ar.pfs,r2
228{ .mii;	alloc		r2=ar.pfs,4,12,0,16
229	cmp4.le		p6,p0=r35,r0	};;
230{ .mfb;	mov		r8=r0			// return value
231(p6)	br.ret.spnt.many	b0	};;
232
233{ .mib;	sub		r10=r35,r0,1
234	.save	ar.lc,r3
235	mov		r3=ar.lc
236	brp.loop.imp	.L_bn_sub_words_ctop,.L_bn_sub_words_cend-16
237					}
238{ .mib;	ADDP		r14=0,r32		// rp
239	.save	pr,r9
240	mov		r9=pr		};;
241	.body
242{ .mii;	ADDP		r15=0,r33		// ap
243	mov		ar.lc=r10
244	mov		ar.ec=6		}
245{ .mib;	ADDP		r16=0,r34		// bp
246	mov		pr.rot=1<<16	};;
247
248.L_bn_sub_words_ctop:
249{ .mii;	(p16)	ld8		r32=[r16],8	  // b=*(bp++)
250	(p18)	sub		r39=r37,r34
251	(p19)	cmp.gtu.unc	p56,p0=r40,r38	}
252{ .mfb;	(p0)	nop.m		0x0
253	(p0)	nop.f		0x0
254	(p0)	nop.b		0x0		}
255{ .mii;	(p16)	ld8		r35=[r15],8	  // a=*(ap++)
256	(p58)	cmp.eq.or	p57,p0=0,r41	  // (p20)
257	(p58)	add		r41=-1,r41	} // (p20)
258{ .mbb;	(p21)	st8		[r14]=r42,8	  // *(rp++)=r
259	(p0)	nop.b		0x0
260	br.ctop.sptk	.L_bn_sub_words_ctop	};;
261.L_bn_sub_words_cend:
262
263{ .mii;
264(p59)	add		r8=1,r8		// return value
265	mov		pr=r9,0x1ffff
266	mov		ar.lc=r3	}
267{ .mbb;	nop.b		0x0
268	br.ret.sptk.many	b0	};;
269.endp	bn_sub_words#
270#endif
271
272#if 0
273#define XMA_TEMPTATION
274#endif
275
276#if 1
277//
278// BN_ULONG bn_mul_words(BN_ULONG *rp, BN_ULONG *ap, int num, BN_ULONG w)
279//
280.global	bn_mul_words#
281.proc	bn_mul_words#
282.align	64
283.skip	32	// makes the loop body aligned at 64-byte boundary
284bn_mul_words:
285	.prologue
286	.save	ar.pfs,r2
287#ifdef XMA_TEMPTATION
288{ .mfi;	alloc		r2=ar.pfs,4,0,0,0	};;
289#else
290{ .mfi;	alloc		r2=ar.pfs,4,12,0,16	};;
291#endif
292{ .mib;	mov		r8=r0			// return value
293	cmp4.le		p6,p0=r34,r0
294(p6)	br.ret.spnt.many	b0		};;
295
296{ .mii;	sub	r10=r34,r0,1
297	.save	ar.lc,r3
298	mov	r3=ar.lc
299	.save	pr,r9
300	mov	r9=pr			};;
301
302	.body
303{ .mib;	setf.sig	f8=r35	// w
304	mov		pr.rot=0x800001<<16
305			// ------^----- serves as (p50) at first (p27)
306	brp.loop.imp	.L_bn_mul_words_ctop,.L_bn_mul_words_cend-16
307					}
308
309#ifndef XMA_TEMPTATION
310
311{ .mmi;	ADDP		r14=0,r32	// rp
312	ADDP		r15=0,r33	// ap
313	mov		ar.lc=r10	}
314{ .mmi;	mov		r40=0		// serves as r35 at first (p27)
315	mov		ar.ec=13	};;
316
317// This loop spins in 2*(n+12) ticks. It's scheduled for data in Itanium
318// L2 cache (i.e. 9 ticks away) as floating point load/store instructions
319// bypass L1 cache and L2 latency is actually best-case scenario for
320// ldf8. The loop is not scalable and shall run in 2*(n+12) even on
321// "wider" IA-64 implementations. It's a trade-off here. n+24 loop
322// would give us ~5% in *overall* performance improvement on "wider"
323// IA-64, but would hurt Itanium for about same because of longer
324// epilogue. As it's a matter of few percents in either case I've
325// chosen to trade the scalability for development time (you can see
326// this very instruction sequence in bn_mul_add_words loop which in
327// turn is scalable).
328.L_bn_mul_words_ctop:
329{ .mfi;	(p25)	getf.sig	r36=f52			// low
330	(p21)	xmpy.lu		f48=f37,f8
331	(p28)	cmp.ltu		p54,p50=r41,r39	}
332{ .mfi;	(p16)	ldf8		f32=[r15],8
333	(p21)	xmpy.hu		f40=f37,f8
334	(p0)	nop.i		0x0		};;
335{ .mii;	(p25)	getf.sig	r32=f44			// high
336	.pred.rel	"mutex",p50,p54
337	(p50)	add		r40=r38,r35		// (p27)
338	(p54)	add		r40=r38,r35,1	}	// (p27)
339{ .mfb;	(p28)	st8		[r14]=r41,8
340	(p0)	nop.f		0x0
341	br.ctop.sptk	.L_bn_mul_words_ctop	};;
342.L_bn_mul_words_cend:
343
344{ .mii;	nop.m		0x0
345.pred.rel	"mutex",p51,p55
346(p51)	add		r8=r36,r0
347(p55)	add		r8=r36,r0,1	}
348{ .mfb;	nop.m	0x0
349	nop.f	0x0
350	nop.b	0x0			}
351
352#else	// XMA_TEMPTATION
353
354	setf.sig	f37=r0	// serves as carry at (p18) tick
355	mov		ar.lc=r10
356	mov		ar.ec=5;;
357
358// Most of you examining this code very likely wonder why in the name
359// of Intel the following loop is commented out? Indeed, it looks so
360// neat that you find it hard to believe that it's something wrong
361// with it, right? The catch is that every iteration depends on the
362// result from previous one and the latter isn't available instantly.
363// The loop therefore spins at the latency of xma minus 1, or in other
364// words at 6*(n+4) ticks:-( Compare to the "production" loop above
365// that runs in 2*(n+11) where the low latency problem is worked around
366// by moving the dependency to one-tick latent interger ALU. Note that
367// "distance" between ldf8 and xma is not latency of ldf8, but the
368// *difference* between xma and ldf8 latencies.
369.L_bn_mul_words_ctop:
370{ .mfi;	(p16)	ldf8		f32=[r33],8
371	(p18)	xma.hu		f38=f34,f8,f39	}
372{ .mfb;	(p20)	stf8		[r32]=f37,8
373	(p18)	xma.lu		f35=f34,f8,f39
374	br.ctop.sptk	.L_bn_mul_words_ctop	};;
375.L_bn_mul_words_cend:
376
377	getf.sig	r8=f41		// the return value
378
379#endif	// XMA_TEMPTATION
380
381{ .mii;	nop.m		0x0
382	mov		pr=r9,0x1ffff
383	mov		ar.lc=r3	}
384{ .mfb;	rum		1<<5		// clear um.mfh
385	nop.f		0x0
386	br.ret.sptk.many	b0	};;
387.endp	bn_mul_words#
388#endif
389
390#if 1
391//
392// BN_ULONG bn_mul_add_words(BN_ULONG *rp, BN_ULONG *ap, int num, BN_ULONG w)
393//
394.global	bn_mul_add_words#
395.proc	bn_mul_add_words#
396.align	64
397.skip	48	// makes the loop body aligned at 64-byte boundary
398bn_mul_add_words:
399	.prologue
400	.save	ar.pfs,r2
401{ .mmi;	alloc		r2=ar.pfs,4,4,0,8
402	cmp4.le		p6,p0=r34,r0
403	.save	ar.lc,r3
404	mov		r3=ar.lc	};;
405{ .mib;	mov		r8=r0		// return value
406	sub		r10=r34,r0,1
407(p6)	br.ret.spnt.many	b0	};;
408
409{ .mib;	setf.sig	f8=r35		// w
410	.save	pr,r9
411	mov		r9=pr
412	brp.loop.imp	.L_bn_mul_add_words_ctop,.L_bn_mul_add_words_cend-16
413					}
414	.body
415{ .mmi;	ADDP		r14=0,r32	// rp
416	ADDP		r15=0,r33	// ap
417	mov		ar.lc=r10	}
418{ .mii;	ADDP		r16=0,r32	// rp copy
419	mov		pr.rot=0x2001<<16
420			// ------^----- serves as (p40) at first (p27)
421	mov		ar.ec=11	};;
422
423// This loop spins in 3*(n+10) ticks on Itanium and in 2*(n+10) on
424// Itanium 2. Yes, unlike previous versions it scales:-) Previous
425// version was peforming *all* additions in IALU and was starving
426// for those even on Itanium 2. In this version one addition is
427// moved to FPU and is folded with multiplication. This is at cost
428// of propogating the result from previous call to this subroutine
429// to L2 cache... In other words negligible even for shorter keys.
430// *Overall* performance improvement [over previous version] varies
431// from 11 to 22 percent depending on key length.
432.L_bn_mul_add_words_ctop:
433.pred.rel	"mutex",p40,p42
434{ .mfi;	(p23)	getf.sig	r36=f45			// low
435	(p20)	xma.lu		f42=f36,f8,f50		// low
436	(p40)	add		r39=r39,r35	}	// (p27)
437{ .mfi;	(p16)	ldf8		f32=[r15],8		// *(ap++)
438	(p20)	xma.hu		f36=f36,f8,f50		// high
439	(p42)	add		r39=r39,r35,1	};;	// (p27)
440{ .mmi;	(p24)	getf.sig	r32=f40			// high
441	(p16)	ldf8		f46=[r16],8		// *(rp1++)
442	(p40)	cmp.ltu		p41,p39=r39,r35	}	// (p27)
443{ .mib;	(p26)	st8		[r14]=r39,8		// *(rp2++)
444	(p42)	cmp.leu		p41,p39=r39,r35		// (p27)
445	br.ctop.sptk	.L_bn_mul_add_words_ctop};;
446.L_bn_mul_add_words_cend:
447
448{ .mmi;	.pred.rel	"mutex",p40,p42
449(p40)	add		r8=r35,r0
450(p42)	add		r8=r35,r0,1
451	mov		pr=r9,0x1ffff	}
452{ .mib;	rum		1<<5		// clear um.mfh
453	mov		ar.lc=r3
454	br.ret.sptk.many	b0	};;
455.endp	bn_mul_add_words#
456#endif
457
458#if 1
459//
460// void bn_sqr_words(BN_ULONG *rp, BN_ULONG *ap, int num)
461//
462.global	bn_sqr_words#
463.proc	bn_sqr_words#
464.align	64
465.skip	32	// makes the loop body aligned at 64-byte boundary
466bn_sqr_words:
467	.prologue
468	.save	ar.pfs,r2
469{ .mii;	alloc		r2=ar.pfs,3,0,0,0
470	sxt4		r34=r34		};;
471{ .mii;	cmp.le		p6,p0=r34,r0
472	mov		r8=r0		}	// return value
473{ .mfb;	ADDP		r32=0,r32
474	nop.f		0x0
475(p6)	br.ret.spnt.many	b0	};;
476
477{ .mii;	sub	r10=r34,r0,1
478	.save	ar.lc,r3
479	mov	r3=ar.lc
480	.save	pr,r9
481	mov	r9=pr			};;
482
483	.body
484{ .mib;	ADDP		r33=0,r33
485	mov		pr.rot=1<<16
486	brp.loop.imp	.L_bn_sqr_words_ctop,.L_bn_sqr_words_cend-16
487					}
488{ .mii;	add		r34=8,r32
489	mov		ar.lc=r10
490	mov		ar.ec=18	};;
491
492// 2*(n+17) on Itanium, (n+17) on "wider" IA-64 implementations. It's
493// possible to compress the epilogue (I'm getting tired to write this
494// comment over and over) and get down to 2*n+16 at the cost of
495// scalability. The decision will very likely be reconsidered after the
496// benchmark program is profiled. I.e. if perfomance gain on Itanium
497// will appear larger than loss on "wider" IA-64, then the loop should
498// be explicitely split and the epilogue compressed.
499.L_bn_sqr_words_ctop:
500{ .mfi;	(p16)	ldf8		f32=[r33],8
501	(p25)	xmpy.lu		f42=f41,f41
502	(p0)	nop.i		0x0		}
503{ .mib;	(p33)	stf8		[r32]=f50,16
504	(p0)	nop.i		0x0
505	(p0)	nop.b		0x0		}
506{ .mfi;	(p0)	nop.m		0x0
507	(p25)	xmpy.hu		f52=f41,f41
508	(p0)	nop.i		0x0		}
509{ .mib;	(p33)	stf8		[r34]=f60,16
510	(p0)	nop.i		0x0
511	br.ctop.sptk	.L_bn_sqr_words_ctop	};;
512.L_bn_sqr_words_cend:
513
514{ .mii;	nop.m		0x0
515	mov		pr=r9,0x1ffff
516	mov		ar.lc=r3	}
517{ .mfb;	rum		1<<5		// clear um.mfh
518	nop.f		0x0
519	br.ret.sptk.many	b0	};;
520.endp	bn_sqr_words#
521#endif
522
523#if 1
524// Apparently we win nothing by implementing special bn_sqr_comba8.
525// Yes, it is possible to reduce the number of multiplications by
526// almost factor of two, but then the amount of additions would
527// increase by factor of two (as we would have to perform those
528// otherwise performed by xma ourselves). Normally we would trade
529// anyway as multiplications are way more expensive, but not this
530// time... Multiplication kernel is fully pipelined and as we drain
531// one 128-bit multiplication result per clock cycle multiplications
532// are effectively as inexpensive as additions. Special implementation
533// might become of interest for "wider" IA-64 implementation as you'll
534// be able to get through the multiplication phase faster (there won't
535// be any stall issues as discussed in the commentary section below and
536// you therefore will be able to employ all 4 FP units)... But these
537// Itanium days it's simply too hard to justify the effort so I just
538// drop down to bn_mul_comba8 code:-)
539//
540// void bn_sqr_comba8(BN_ULONG *r, BN_ULONG *a)
541//
542.global	bn_sqr_comba8#
543.proc	bn_sqr_comba8#
544.align	64
545bn_sqr_comba8:
546	.prologue
547	.save	ar.pfs,r2
548#if defined(_HPUX_SOURCE) && !defined(_LP64)
549{ .mii;	alloc	r2=ar.pfs,2,1,0,0
550	addp4	r33=0,r33
551	addp4	r32=0,r32		};;
552{ .mii;
553#else
554{ .mii;	alloc	r2=ar.pfs,2,1,0,0
555#endif
556	mov	r34=r33
557	add	r14=8,r33		};;
558	.body
559{ .mii;	add	r17=8,r34
560	add	r15=16,r33
561	add	r18=16,r34		}
562{ .mfb;	add	r16=24,r33
563	br	.L_cheat_entry_point8	};;
564.endp	bn_sqr_comba8#
565#endif
566
567#if 1
568// I've estimated this routine to run in ~120 ticks, but in reality
569// (i.e. according to ar.itc) it takes ~160 ticks. Are those extra
570// cycles consumed for instructions fetch? Or did I misinterpret some
571// clause in Itanium �-architecture manual? Comments are welcomed and
572// highly appreciated.
573//
574// On Itanium 2 it takes ~190 ticks. This is because of stalls on
575// result from getf.sig. I do nothing about it at this point for
576// reasons depicted below.
577//
578// However! It should be noted that even 160 ticks is darn good result
579// as it's over 10 (yes, ten, spelled as t-e-n) times faster than the
580// C version (compiled with gcc with inline assembler). I really
581// kicked compiler's butt here, didn't I? Yeah! This brings us to the
582// following statement. It's damn shame that this routine isn't called
583// very often nowadays! According to the profiler most CPU time is
584// consumed by bn_mul_add_words called from BN_from_montgomery. In
585// order to estimate what we're missing, I've compared the performance
586// of this routine against "traditional" implementation, i.e. against
587// following routine:
588//
589// void bn_mul_comba8(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)
590// {	r[ 8]=bn_mul_words(    &(r[0]),a,8,b[0]);
591//	r[ 9]=bn_mul_add_words(&(r[1]),a,8,b[1]);
592//	r[10]=bn_mul_add_words(&(r[2]),a,8,b[2]);
593//	r[11]=bn_mul_add_words(&(r[3]),a,8,b[3]);
594//	r[12]=bn_mul_add_words(&(r[4]),a,8,b[4]);
595//	r[13]=bn_mul_add_words(&(r[5]),a,8,b[5]);
596//	r[14]=bn_mul_add_words(&(r[6]),a,8,b[6]);
597//	r[15]=bn_mul_add_words(&(r[7]),a,8,b[7]);
598// }
599//
600// The one below is over 8 times faster than the one above:-( Even
601// more reasons to "combafy" bn_mul_add_mont...
602//
603// And yes, this routine really made me wish there were an optimizing
604// assembler! It also feels like it deserves a dedication.
605//
606//	To my wife for being there and to my kids...
607//
608// void bn_mul_comba8(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)
609//
610#define	carry1	r14
611#define	carry2	r15
612#define	carry3	r34
613.global	bn_mul_comba8#
614.proc	bn_mul_comba8#
615.align	64
616bn_mul_comba8:
617	.prologue
618	.save	ar.pfs,r2
619#if defined(_HPUX_SOURCE) && !defined(_LP64)
620{ .mii;	alloc	r2=ar.pfs,3,0,0,0
621	addp4	r33=0,r33
622	addp4	r34=0,r34		};;
623{ .mii;	addp4	r32=0,r32
624#else
625{ .mii;	alloc   r2=ar.pfs,3,0,0,0
626#endif
627	add	r14=8,r33
628	add	r17=8,r34		}
629	.body
630{ .mii;	add	r15=16,r33
631	add	r18=16,r34
632	add	r16=24,r33		}
633.L_cheat_entry_point8:
634{ .mmi;	add	r19=24,r34
635
636	ldf8	f32=[r33],32		};;
637
638{ .mmi;	ldf8	f120=[r34],32
639	ldf8	f121=[r17],32		}
640{ .mmi;	ldf8	f122=[r18],32
641	ldf8	f123=[r19],32		};;
642{ .mmi;	ldf8	f124=[r34]
643	ldf8	f125=[r17]		}
644{ .mmi;	ldf8	f126=[r18]
645	ldf8	f127=[r19]		}
646
647{ .mmi;	ldf8	f33=[r14],32
648	ldf8	f34=[r15],32		}
649{ .mmi;	ldf8	f35=[r16],32;;
650	ldf8	f36=[r33]		}
651{ .mmi;	ldf8	f37=[r14]
652	ldf8	f38=[r15]		}
653{ .mfi;	ldf8	f39=[r16]
654// -------\ Entering multiplier's heaven /-------
655// ------------\                    /------------
656// -----------------\          /-----------------
657// ----------------------\/----------------------
658		xma.hu	f41=f32,f120,f0		}
659{ .mfi;		xma.lu	f40=f32,f120,f0		};; // (*)
660{ .mfi;		xma.hu	f51=f32,f121,f0		}
661{ .mfi;		xma.lu	f50=f32,f121,f0		};;
662{ .mfi;		xma.hu	f61=f32,f122,f0		}
663{ .mfi;		xma.lu	f60=f32,f122,f0		};;
664{ .mfi;		xma.hu	f71=f32,f123,f0		}
665{ .mfi;		xma.lu	f70=f32,f123,f0		};;
666{ .mfi;		xma.hu	f81=f32,f124,f0		}
667{ .mfi;		xma.lu	f80=f32,f124,f0		};;
668{ .mfi;		xma.hu	f91=f32,f125,f0		}
669{ .mfi;		xma.lu	f90=f32,f125,f0		};;
670{ .mfi;		xma.hu	f101=f32,f126,f0	}
671{ .mfi;		xma.lu	f100=f32,f126,f0	};;
672{ .mfi;		xma.hu	f111=f32,f127,f0	}
673{ .mfi;		xma.lu	f110=f32,f127,f0	};;//
674// (*)	You can argue that splitting at every second bundle would
675//	prevent "wider" IA-64 implementations from achieving the peak
676//	performance. Well, not really... The catch is that if you
677//	intend to keep 4 FP units busy by splitting at every fourth
678//	bundle and thus perform these 16 multiplications in 4 ticks,
679//	the first bundle *below* would stall because the result from
680//	the first xma bundle *above* won't be available for another 3
681//	ticks (if not more, being an optimist, I assume that "wider"
682//	implementation will have same latency:-). This stall will hold
683//	you back and the performance would be as if every second bundle
684//	were split *anyway*...
685{ .mfi;	getf.sig	r16=f40
686		xma.hu	f42=f33,f120,f41
687	add		r33=8,r32		}
688{ .mfi;		xma.lu	f41=f33,f120,f41	};;
689{ .mfi;	getf.sig	r24=f50
690		xma.hu	f52=f33,f121,f51	}
691{ .mfi;		xma.lu	f51=f33,f121,f51	};;
692{ .mfi;	st8		[r32]=r16,16
693		xma.hu	f62=f33,f122,f61	}
694{ .mfi;		xma.lu	f61=f33,f122,f61	};;
695{ .mfi;		xma.hu	f72=f33,f123,f71	}
696{ .mfi;		xma.lu	f71=f33,f123,f71	};;
697{ .mfi;		xma.hu	f82=f33,f124,f81	}
698{ .mfi;		xma.lu	f81=f33,f124,f81	};;
699{ .mfi;		xma.hu	f92=f33,f125,f91	}
700{ .mfi;		xma.lu	f91=f33,f125,f91	};;
701{ .mfi;		xma.hu	f102=f33,f126,f101	}
702{ .mfi;		xma.lu	f101=f33,f126,f101	};;
703{ .mfi;		xma.hu	f112=f33,f127,f111	}
704{ .mfi;		xma.lu	f111=f33,f127,f111	};;//
705//-------------------------------------------------//
706{ .mfi;	getf.sig	r25=f41
707		xma.hu	f43=f34,f120,f42	}
708{ .mfi;		xma.lu	f42=f34,f120,f42	};;
709{ .mfi;	getf.sig	r16=f60
710		xma.hu	f53=f34,f121,f52	}
711{ .mfi;		xma.lu	f52=f34,f121,f52	};;
712{ .mfi;	getf.sig	r17=f51
713		xma.hu	f63=f34,f122,f62
714	add		r25=r25,r24		}
715{ .mfi;		xma.lu	f62=f34,f122,f62
716	mov		carry1=0		};;
717{ .mfi;	cmp.ltu		p6,p0=r25,r24
718		xma.hu	f73=f34,f123,f72	}
719{ .mfi;		xma.lu	f72=f34,f123,f72	};;
720{ .mfi;	st8		[r33]=r25,16
721		xma.hu	f83=f34,f124,f82
722(p6)	add		carry1=1,carry1		}
723{ .mfi;		xma.lu	f82=f34,f124,f82	};;
724{ .mfi;		xma.hu	f93=f34,f125,f92	}
725{ .mfi;		xma.lu	f92=f34,f125,f92	};;
726{ .mfi;		xma.hu	f103=f34,f126,f102	}
727{ .mfi;		xma.lu	f102=f34,f126,f102	};;
728{ .mfi;		xma.hu	f113=f34,f127,f112	}
729{ .mfi;		xma.lu	f112=f34,f127,f112	};;//
730//-------------------------------------------------//
731{ .mfi;	getf.sig	r18=f42
732		xma.hu	f44=f35,f120,f43
733	add		r17=r17,r16		}
734{ .mfi;		xma.lu	f43=f35,f120,f43	};;
735{ .mfi;	getf.sig	r24=f70
736		xma.hu	f54=f35,f121,f53	}
737{ .mfi;	mov		carry2=0
738		xma.lu	f53=f35,f121,f53	};;
739{ .mfi;	getf.sig	r25=f61
740		xma.hu	f64=f35,f122,f63
741	cmp.ltu		p7,p0=r17,r16		}
742{ .mfi;	add		r18=r18,r17
743		xma.lu	f63=f35,f122,f63	};;
744{ .mfi;	getf.sig	r26=f52
745		xma.hu	f74=f35,f123,f73
746(p7)	add		carry2=1,carry2		}
747{ .mfi;	cmp.ltu		p7,p0=r18,r17
748		xma.lu	f73=f35,f123,f73
749	add		r18=r18,carry1		};;
750{ .mfi;
751		xma.hu	f84=f35,f124,f83
752(p7)	add		carry2=1,carry2		}
753{ .mfi;	cmp.ltu		p7,p0=r18,carry1
754		xma.lu	f83=f35,f124,f83	};;
755{ .mfi;	st8		[r32]=r18,16
756		xma.hu	f94=f35,f125,f93
757(p7)	add		carry2=1,carry2		}
758{ .mfi;		xma.lu	f93=f35,f125,f93	};;
759{ .mfi;		xma.hu	f104=f35,f126,f103	}
760{ .mfi;		xma.lu	f103=f35,f126,f103	};;
761{ .mfi;		xma.hu	f114=f35,f127,f113	}
762{ .mfi;	mov		carry1=0
763		xma.lu	f113=f35,f127,f113
764	add		r25=r25,r24		};;//
765//-------------------------------------------------//
766{ .mfi;	getf.sig	r27=f43
767		xma.hu	f45=f36,f120,f44
768	cmp.ltu		p6,p0=r25,r24		}
769{ .mfi;		xma.lu	f44=f36,f120,f44
770	add		r26=r26,r25		};;
771{ .mfi;	getf.sig	r16=f80
772		xma.hu	f55=f36,f121,f54
773(p6)	add		carry1=1,carry1		}
774{ .mfi;		xma.lu	f54=f36,f121,f54	};;
775{ .mfi;	getf.sig	r17=f71
776		xma.hu	f65=f36,f122,f64
777	cmp.ltu		p6,p0=r26,r25		}
778{ .mfi;		xma.lu	f64=f36,f122,f64
779	add		r27=r27,r26		};;
780{ .mfi;	getf.sig	r18=f62
781		xma.hu	f75=f36,f123,f74
782(p6)	add		carry1=1,carry1		}
783{ .mfi;	cmp.ltu		p6,p0=r27,r26
784		xma.lu	f74=f36,f123,f74
785	add		r27=r27,carry2		};;
786{ .mfi;	getf.sig	r19=f53
787		xma.hu	f85=f36,f124,f84
788(p6)	add		carry1=1,carry1		}
789{ .mfi;		xma.lu	f84=f36,f124,f84
790	cmp.ltu		p6,p0=r27,carry2	};;
791{ .mfi;	st8		[r33]=r27,16
792		xma.hu	f95=f36,f125,f94
793(p6)	add		carry1=1,carry1		}
794{ .mfi;		xma.lu	f94=f36,f125,f94	};;
795{ .mfi;		xma.hu	f105=f36,f126,f104	}
796{ .mfi;	mov		carry2=0
797		xma.lu	f104=f36,f126,f104
798	add		r17=r17,r16		};;
799{ .mfi;		xma.hu	f115=f36,f127,f114
800	cmp.ltu		p7,p0=r17,r16		}
801{ .mfi;		xma.lu	f114=f36,f127,f114
802	add		r18=r18,r17		};;//
803//-------------------------------------------------//
804{ .mfi;	getf.sig	r20=f44
805		xma.hu	f46=f37,f120,f45
806(p7)	add		carry2=1,carry2		}
807{ .mfi;	cmp.ltu		p7,p0=r18,r17
808		xma.lu	f45=f37,f120,f45
809	add		r19=r19,r18		};;
810{ .mfi;	getf.sig	r24=f90
811		xma.hu	f56=f37,f121,f55	}
812{ .mfi;		xma.lu	f55=f37,f121,f55	};;
813{ .mfi;	getf.sig	r25=f81
814		xma.hu	f66=f37,f122,f65
815(p7)	add		carry2=1,carry2		}
816{ .mfi;	cmp.ltu		p7,p0=r19,r18
817		xma.lu	f65=f37,f122,f65
818	add		r20=r20,r19		};;
819{ .mfi;	getf.sig	r26=f72
820		xma.hu	f76=f37,f123,f75
821(p7)	add		carry2=1,carry2		}
822{ .mfi;	cmp.ltu		p7,p0=r20,r19
823		xma.lu	f75=f37,f123,f75
824	add		r20=r20,carry1		};;
825{ .mfi;	getf.sig	r27=f63
826		xma.hu	f86=f37,f124,f85
827(p7)	add		carry2=1,carry2		}
828{ .mfi;		xma.lu	f85=f37,f124,f85
829	cmp.ltu		p7,p0=r20,carry1	};;
830{ .mfi;	getf.sig	r28=f54
831		xma.hu	f96=f37,f125,f95
832(p7)	add		carry2=1,carry2		}
833{ .mfi;	st8		[r32]=r20,16
834		xma.lu	f95=f37,f125,f95	};;
835{ .mfi;		xma.hu	f106=f37,f126,f105	}
836{ .mfi;	mov		carry1=0
837		xma.lu	f105=f37,f126,f105
838	add		r25=r25,r24		};;
839{ .mfi;		xma.hu	f116=f37,f127,f115
840	cmp.ltu		p6,p0=r25,r24		}
841{ .mfi;		xma.lu	f115=f37,f127,f115
842	add		r26=r26,r25		};;//
843//-------------------------------------------------//
844{ .mfi;	getf.sig	r29=f45
845		xma.hu	f47=f38,f120,f46
846(p6)	add		carry1=1,carry1		}
847{ .mfi;	cmp.ltu		p6,p0=r26,r25
848		xma.lu	f46=f38,f120,f46
849	add		r27=r27,r26		};;
850{ .mfi;	getf.sig	r16=f100
851		xma.hu	f57=f38,f121,f56
852(p6)	add		carry1=1,carry1		}
853{ .mfi;	cmp.ltu		p6,p0=r27,r26
854		xma.lu	f56=f38,f121,f56
855	add		r28=r28,r27		};;
856{ .mfi;	getf.sig	r17=f91
857		xma.hu	f67=f38,f122,f66
858(p6)	add		carry1=1,carry1		}
859{ .mfi;	cmp.ltu		p6,p0=r28,r27
860		xma.lu	f66=f38,f122,f66
861	add		r29=r29,r28		};;
862{ .mfi;	getf.sig	r18=f82
863		xma.hu	f77=f38,f123,f76
864(p6)	add		carry1=1,carry1		}
865{ .mfi;	cmp.ltu		p6,p0=r29,r28
866		xma.lu	f76=f38,f123,f76
867	add		r29=r29,carry2		};;
868{ .mfi;	getf.sig	r19=f73
869		xma.hu	f87=f38,f124,f86
870(p6)	add		carry1=1,carry1		}
871{ .mfi;		xma.lu	f86=f38,f124,f86
872	cmp.ltu		p6,p0=r29,carry2	};;
873{ .mfi;	getf.sig	r20=f64
874		xma.hu	f97=f38,f125,f96
875(p6)	add		carry1=1,carry1		}
876{ .mfi;	st8		[r33]=r29,16
877		xma.lu	f96=f38,f125,f96	};;
878{ .mfi;	getf.sig	r21=f55
879		xma.hu	f107=f38,f126,f106	}
880{ .mfi;	mov		carry2=0
881		xma.lu	f106=f38,f126,f106
882	add		r17=r17,r16		};;
883{ .mfi;		xma.hu	f117=f38,f127,f116
884	cmp.ltu		p7,p0=r17,r16		}
885{ .mfi;		xma.lu	f116=f38,f127,f116
886	add		r18=r18,r17		};;//
887//-------------------------------------------------//
888{ .mfi;	getf.sig	r22=f46
889		xma.hu	f48=f39,f120,f47
890(p7)	add		carry2=1,carry2		}
891{ .mfi;	cmp.ltu		p7,p0=r18,r17
892		xma.lu	f47=f39,f120,f47
893	add		r19=r19,r18		};;
894{ .mfi;	getf.sig	r24=f110
895		xma.hu	f58=f39,f121,f57
896(p7)	add		carry2=1,carry2		}
897{ .mfi;	cmp.ltu		p7,p0=r19,r18
898		xma.lu	f57=f39,f121,f57
899	add		r20=r20,r19		};;
900{ .mfi;	getf.sig	r25=f101
901		xma.hu	f68=f39,f122,f67
902(p7)	add		carry2=1,carry2		}
903{ .mfi;	cmp.ltu		p7,p0=r20,r19
904		xma.lu	f67=f39,f122,f67
905	add		r21=r21,r20		};;
906{ .mfi;	getf.sig	r26=f92
907		xma.hu	f78=f39,f123,f77
908(p7)	add		carry2=1,carry2		}
909{ .mfi;	cmp.ltu		p7,p0=r21,r20
910		xma.lu	f77=f39,f123,f77
911	add		r22=r22,r21		};;
912{ .mfi;	getf.sig	r27=f83
913		xma.hu	f88=f39,f124,f87
914(p7)	add		carry2=1,carry2		}
915{ .mfi;	cmp.ltu		p7,p0=r22,r21
916		xma.lu	f87=f39,f124,f87
917	add		r22=r22,carry1		};;
918{ .mfi;	getf.sig	r28=f74
919		xma.hu	f98=f39,f125,f97
920(p7)	add		carry2=1,carry2		}
921{ .mfi;		xma.lu	f97=f39,f125,f97
922	cmp.ltu		p7,p0=r22,carry1	};;
923{ .mfi;	getf.sig	r29=f65
924		xma.hu	f108=f39,f126,f107
925(p7)	add		carry2=1,carry2		}
926{ .mfi;	st8		[r32]=r22,16
927		xma.lu	f107=f39,f126,f107	};;
928{ .mfi;	getf.sig	r30=f56
929		xma.hu	f118=f39,f127,f117	}
930{ .mfi;		xma.lu	f117=f39,f127,f117	};;//
931//-------------------------------------------------//
932// Leaving muliplier's heaven... Quite a ride, huh?
933
934{ .mii;	getf.sig	r31=f47
935	add		r25=r25,r24
936	mov		carry1=0		};;
937{ .mii;		getf.sig	r16=f111
938	cmp.ltu		p6,p0=r25,r24
939	add		r26=r26,r25		};;
940{ .mfb;		getf.sig	r17=f102	}
941{ .mii;
942(p6)	add		carry1=1,carry1
943	cmp.ltu		p6,p0=r26,r25
944	add		r27=r27,r26		};;
945{ .mfb;	nop.m	0x0				}
946{ .mii;
947(p6)	add		carry1=1,carry1
948	cmp.ltu		p6,p0=r27,r26
949	add		r28=r28,r27		};;
950{ .mii;		getf.sig	r18=f93
951		add		r17=r17,r16
952		mov		carry3=0	}
953{ .mii;
954(p6)	add		carry1=1,carry1
955	cmp.ltu		p6,p0=r28,r27
956	add		r29=r29,r28		};;
957{ .mii;		getf.sig	r19=f84
958		cmp.ltu		p7,p0=r17,r16	}
959{ .mii;
960(p6)	add		carry1=1,carry1
961	cmp.ltu		p6,p0=r29,r28
962	add		r30=r30,r29		};;
963{ .mii;		getf.sig	r20=f75
964		add		r18=r18,r17	}
965{ .mii;
966(p6)	add		carry1=1,carry1
967	cmp.ltu		p6,p0=r30,r29
968	add		r31=r31,r30		};;
969{ .mfb;		getf.sig	r21=f66		}
970{ .mii;	(p7)	add		carry3=1,carry3
971		cmp.ltu		p7,p0=r18,r17
972		add		r19=r19,r18	}
973{ .mfb;	nop.m	0x0				}
974{ .mii;
975(p6)	add		carry1=1,carry1
976	cmp.ltu		p6,p0=r31,r30
977	add		r31=r31,carry2		};;
978{ .mfb;		getf.sig	r22=f57		}
979{ .mii;	(p7)	add		carry3=1,carry3
980		cmp.ltu		p7,p0=r19,r18
981		add		r20=r20,r19	}
982{ .mfb;	nop.m	0x0				}
983{ .mii;
984(p6)	add		carry1=1,carry1
985	cmp.ltu		p6,p0=r31,carry2	};;
986{ .mfb;		getf.sig	r23=f48		}
987{ .mii;	(p7)	add		carry3=1,carry3
988		cmp.ltu		p7,p0=r20,r19
989		add		r21=r21,r20	}
990{ .mii;
991(p6)	add		carry1=1,carry1		}
992{ .mfb;	st8		[r33]=r31,16		};;
993
994{ .mfb;	getf.sig	r24=f112		}
995{ .mii;	(p7)	add		carry3=1,carry3
996		cmp.ltu		p7,p0=r21,r20
997		add		r22=r22,r21	};;
998{ .mfb;	getf.sig	r25=f103		}
999{ .mii;	(p7)	add		carry3=1,carry3
1000		cmp.ltu		p7,p0=r22,r21
1001		add		r23=r23,r22	};;
1002{ .mfb;	getf.sig	r26=f94			}
1003{ .mii;	(p7)	add		carry3=1,carry3
1004		cmp.ltu		p7,p0=r23,r22
1005		add		r23=r23,carry1	};;
1006{ .mfb;	getf.sig	r27=f85			}
1007{ .mii;	(p7)	add		carry3=1,carry3
1008		cmp.ltu		p7,p8=r23,carry1};;
1009{ .mii;	getf.sig	r28=f76
1010	add		r25=r25,r24
1011	mov		carry1=0		}
1012{ .mii;		st8		[r32]=r23,16
1013	(p7)	add		carry2=1,carry3
1014	(p8)	add		carry2=0,carry3	};;
1015
1016{ .mfb;	nop.m	0x0				}
1017{ .mii;	getf.sig	r29=f67
1018	cmp.ltu		p6,p0=r25,r24
1019	add		r26=r26,r25		};;
1020{ .mfb;	getf.sig	r30=f58			}
1021{ .mii;
1022(p6)	add		carry1=1,carry1
1023	cmp.ltu		p6,p0=r26,r25
1024	add		r27=r27,r26		};;
1025{ .mfb;		getf.sig	r16=f113	}
1026{ .mii;
1027(p6)	add		carry1=1,carry1
1028	cmp.ltu		p6,p0=r27,r26
1029	add		r28=r28,r27		};;
1030{ .mfb;		getf.sig	r17=f104	}
1031{ .mii;
1032(p6)	add		carry1=1,carry1
1033	cmp.ltu		p6,p0=r28,r27
1034	add		r29=r29,r28		};;
1035{ .mfb;		getf.sig	r18=f95		}
1036{ .mii;
1037(p6)	add		carry1=1,carry1
1038	cmp.ltu		p6,p0=r29,r28
1039	add		r30=r30,r29		};;
1040{ .mii;		getf.sig	r19=f86
1041		add		r17=r17,r16
1042		mov		carry3=0	}
1043{ .mii;
1044(p6)	add		carry1=1,carry1
1045	cmp.ltu		p6,p0=r30,r29
1046	add		r30=r30,carry2		};;
1047{ .mii;		getf.sig	r20=f77
1048		cmp.ltu		p7,p0=r17,r16
1049		add		r18=r18,r17	}
1050{ .mii;
1051(p6)	add		carry1=1,carry1
1052	cmp.ltu		p6,p0=r30,carry2	};;
1053{ .mfb;		getf.sig	r21=f68		}
1054{ .mii;	st8		[r33]=r30,16
1055(p6)	add		carry1=1,carry1		};;
1056
1057{ .mfb;	getf.sig	r24=f114		}
1058{ .mii;	(p7)	add		carry3=1,carry3
1059		cmp.ltu		p7,p0=r18,r17
1060		add		r19=r19,r18	};;
1061{ .mfb;	getf.sig	r25=f105		}
1062{ .mii;	(p7)	add		carry3=1,carry3
1063		cmp.ltu		p7,p0=r19,r18
1064		add		r20=r20,r19	};;
1065{ .mfb;	getf.sig	r26=f96			}
1066{ .mii;	(p7)	add		carry3=1,carry3
1067		cmp.ltu		p7,p0=r20,r19
1068		add		r21=r21,r20	};;
1069{ .mfb;	getf.sig	r27=f87			}
1070{ .mii;	(p7)	add		carry3=1,carry3
1071		cmp.ltu		p7,p0=r21,r20
1072		add		r21=r21,carry1	};;
1073{ .mib;	getf.sig	r28=f78
1074	add		r25=r25,r24		}
1075{ .mib;	(p7)	add		carry3=1,carry3
1076		cmp.ltu		p7,p8=r21,carry1};;
1077{ .mii;		st8		[r32]=r21,16
1078	(p7)	add		carry2=1,carry3
1079	(p8)	add		carry2=0,carry3	}
1080
1081{ .mii;	mov		carry1=0
1082	cmp.ltu		p6,p0=r25,r24
1083	add		r26=r26,r25		};;
1084{ .mfb;		getf.sig	r16=f115	}
1085{ .mii;
1086(p6)	add		carry1=1,carry1
1087	cmp.ltu		p6,p0=r26,r25
1088	add		r27=r27,r26		};;
1089{ .mfb;		getf.sig	r17=f106	}
1090{ .mii;
1091(p6)	add		carry1=1,carry1
1092	cmp.ltu		p6,p0=r27,r26
1093	add		r28=r28,r27		};;
1094{ .mfb;		getf.sig	r18=f97		}
1095{ .mii;
1096(p6)	add		carry1=1,carry1
1097	cmp.ltu		p6,p0=r28,r27
1098	add		r28=r28,carry2		};;
1099{ .mib;		getf.sig	r19=f88
1100		add		r17=r17,r16	}
1101{ .mib;
1102(p6)	add		carry1=1,carry1
1103	cmp.ltu		p6,p0=r28,carry2	};;
1104{ .mii;	st8		[r33]=r28,16
1105(p6)	add		carry1=1,carry1		}
1106
1107{ .mii;		mov		carry2=0
1108		cmp.ltu		p7,p0=r17,r16
1109		add		r18=r18,r17	};;
1110{ .mfb;	getf.sig	r24=f116		}
1111{ .mii;	(p7)	add		carry2=1,carry2
1112		cmp.ltu		p7,p0=r18,r17
1113		add		r19=r19,r18	};;
1114{ .mfb;	getf.sig	r25=f107		}
1115{ .mii;	(p7)	add		carry2=1,carry2
1116		cmp.ltu		p7,p0=r19,r18
1117		add		r19=r19,carry1	};;
1118{ .mfb;	getf.sig	r26=f98			}
1119{ .mii;	(p7)	add		carry2=1,carry2
1120		cmp.ltu		p7,p0=r19,carry1};;
1121{ .mii;		st8		[r32]=r19,16
1122	(p7)	add		carry2=1,carry2	}
1123
1124{ .mfb;	add		r25=r25,r24		};;
1125
1126{ .mfb;		getf.sig	r16=f117	}
1127{ .mii;	mov		carry1=0
1128	cmp.ltu		p6,p0=r25,r24
1129	add		r26=r26,r25		};;
1130{ .mfb;		getf.sig	r17=f108	}
1131{ .mii;
1132(p6)	add		carry1=1,carry1
1133	cmp.ltu		p6,p0=r26,r25
1134	add		r26=r26,carry2		};;
1135{ .mfb;	nop.m	0x0				}
1136{ .mii;
1137(p6)	add		carry1=1,carry1
1138	cmp.ltu		p6,p0=r26,carry2	};;
1139{ .mii;	st8		[r33]=r26,16
1140(p6)	add		carry1=1,carry1		}
1141
1142{ .mfb;		add		r17=r17,r16	};;
1143{ .mfb;	getf.sig	r24=f118		}
1144{ .mii;		mov		carry2=0
1145		cmp.ltu		p7,p0=r17,r16
1146		add		r17=r17,carry1	};;
1147{ .mii;	(p7)	add		carry2=1,carry2
1148		cmp.ltu		p7,p0=r17,carry1};;
1149{ .mii;		st8		[r32]=r17
1150	(p7)	add		carry2=1,carry2	};;
1151{ .mfb;	add		r24=r24,carry2		};;
1152{ .mib;	st8		[r33]=r24		}
1153
1154{ .mib;	rum		1<<5		// clear um.mfh
1155	br.ret.sptk.many	b0	};;
1156.endp	bn_mul_comba8#
1157#undef	carry3
1158#undef	carry2
1159#undef	carry1
1160#endif
1161
1162#if 1
1163// It's possible to make it faster (see comment to bn_sqr_comba8), but
1164// I reckon it doesn't worth the effort. Basically because the routine
1165// (actually both of them) practically never called... So I just play
1166// same trick as with bn_sqr_comba8.
1167//
1168// void bn_sqr_comba4(BN_ULONG *r, BN_ULONG *a)
1169//
1170.global	bn_sqr_comba4#
1171.proc	bn_sqr_comba4#
1172.align	64
1173bn_sqr_comba4:
1174	.prologue
1175	.save	ar.pfs,r2
1176#if defined(_HPUX_SOURCE) && !defined(_LP64)
1177{ .mii;	alloc   r2=ar.pfs,2,1,0,0
1178	addp4	r32=0,r32
1179	addp4	r33=0,r33		};;
1180{ .mii;
1181#else
1182{ .mii;	alloc	r2=ar.pfs,2,1,0,0
1183#endif
1184	mov	r34=r33
1185	add	r14=8,r33		};;
1186	.body
1187{ .mii;	add	r17=8,r34
1188	add	r15=16,r33
1189	add	r18=16,r34		}
1190{ .mfb;	add	r16=24,r33
1191	br	.L_cheat_entry_point4	};;
1192.endp	bn_sqr_comba4#
1193#endif
1194
1195#if 1
1196// Runs in ~115 cycles and ~4.5 times faster than C. Well, whatever...
1197//
1198// void bn_mul_comba4(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)
1199//
1200#define	carry1	r14
1201#define	carry2	r15
1202.global	bn_mul_comba4#
1203.proc	bn_mul_comba4#
1204.align	64
1205bn_mul_comba4:
1206	.prologue
1207	.save	ar.pfs,r2
1208#if defined(_HPUX_SOURCE) && !defined(_LP64)
1209{ .mii;	alloc   r2=ar.pfs,3,0,0,0
1210	addp4	r33=0,r33
1211	addp4	r34=0,r34		};;
1212{ .mii;	addp4	r32=0,r32
1213#else
1214{ .mii;	alloc	r2=ar.pfs,3,0,0,0
1215#endif
1216	add	r14=8,r33
1217	add	r17=8,r34		}
1218	.body
1219{ .mii;	add	r15=16,r33
1220	add	r18=16,r34
1221	add	r16=24,r33		};;
1222.L_cheat_entry_point4:
1223{ .mmi;	add	r19=24,r34
1224
1225	ldf8	f32=[r33]		}
1226
1227{ .mmi;	ldf8	f120=[r34]
1228	ldf8	f121=[r17]		};;
1229{ .mmi;	ldf8	f122=[r18]
1230	ldf8	f123=[r19]		}
1231
1232{ .mmi;	ldf8	f33=[r14]
1233	ldf8	f34=[r15]		}
1234{ .mfi;	ldf8	f35=[r16]
1235
1236		xma.hu	f41=f32,f120,f0		}
1237{ .mfi;		xma.lu	f40=f32,f120,f0		};;
1238{ .mfi;		xma.hu	f51=f32,f121,f0		}
1239{ .mfi;		xma.lu	f50=f32,f121,f0		};;
1240{ .mfi;		xma.hu	f61=f32,f122,f0		}
1241{ .mfi;		xma.lu	f60=f32,f122,f0		};;
1242{ .mfi;		xma.hu	f71=f32,f123,f0		}
1243{ .mfi;		xma.lu	f70=f32,f123,f0		};;//
1244// Major stall takes place here, and 3 more places below. Result from
1245// first xma is not available for another 3 ticks.
1246{ .mfi;	getf.sig	r16=f40
1247		xma.hu	f42=f33,f120,f41
1248	add		r33=8,r32		}
1249{ .mfi;		xma.lu	f41=f33,f120,f41	};;
1250{ .mfi;	getf.sig	r24=f50
1251		xma.hu	f52=f33,f121,f51	}
1252{ .mfi;		xma.lu	f51=f33,f121,f51	};;
1253{ .mfi;	st8		[r32]=r16,16
1254		xma.hu	f62=f33,f122,f61	}
1255{ .mfi;		xma.lu	f61=f33,f122,f61	};;
1256{ .mfi;		xma.hu	f72=f33,f123,f71	}
1257{ .mfi;		xma.lu	f71=f33,f123,f71	};;//
1258//-------------------------------------------------//
1259{ .mfi;	getf.sig	r25=f41
1260		xma.hu	f43=f34,f120,f42	}
1261{ .mfi;		xma.lu	f42=f34,f120,f42	};;
1262{ .mfi;	getf.sig	r16=f60
1263		xma.hu	f53=f34,f121,f52	}
1264{ .mfi;		xma.lu	f52=f34,f121,f52	};;
1265{ .mfi;	getf.sig	r17=f51
1266		xma.hu	f63=f34,f122,f62
1267	add		r25=r25,r24		}
1268{ .mfi;	mov		carry1=0
1269		xma.lu	f62=f34,f122,f62	};;
1270{ .mfi;	st8		[r33]=r25,16
1271		xma.hu	f73=f34,f123,f72
1272	cmp.ltu		p6,p0=r25,r24		}
1273{ .mfi;		xma.lu	f72=f34,f123,f72	};;//
1274//-------------------------------------------------//
1275{ .mfi;	getf.sig	r18=f42
1276		xma.hu	f44=f35,f120,f43
1277(p6)	add		carry1=1,carry1		}
1278{ .mfi;	add		r17=r17,r16
1279		xma.lu	f43=f35,f120,f43
1280	mov		carry2=0		};;
1281{ .mfi;	getf.sig	r24=f70
1282		xma.hu	f54=f35,f121,f53
1283	cmp.ltu		p7,p0=r17,r16		}
1284{ .mfi;		xma.lu	f53=f35,f121,f53	};;
1285{ .mfi;	getf.sig	r25=f61
1286		xma.hu	f64=f35,f122,f63
1287	add		r18=r18,r17		}
1288{ .mfi;		xma.lu	f63=f35,f122,f63
1289(p7)	add		carry2=1,carry2		};;
1290{ .mfi;	getf.sig	r26=f52
1291		xma.hu	f74=f35,f123,f73
1292	cmp.ltu		p7,p0=r18,r17		}
1293{ .mfi;		xma.lu	f73=f35,f123,f73
1294	add		r18=r18,carry1		};;
1295//-------------------------------------------------//
1296{ .mii;	st8		[r32]=r18,16
1297(p7)	add		carry2=1,carry2
1298	cmp.ltu		p7,p0=r18,carry1	};;
1299
1300{ .mfi;	getf.sig	r27=f43	// last major stall
1301(p7)	add		carry2=1,carry2		};;
1302{ .mii;		getf.sig	r16=f71
1303	add		r25=r25,r24
1304	mov		carry1=0		};;
1305{ .mii;		getf.sig	r17=f62
1306	cmp.ltu		p6,p0=r25,r24
1307	add		r26=r26,r25		};;
1308{ .mii;
1309(p6)	add		carry1=1,carry1
1310	cmp.ltu		p6,p0=r26,r25
1311	add		r27=r27,r26		};;
1312{ .mii;
1313(p6)	add		carry1=1,carry1
1314	cmp.ltu		p6,p0=r27,r26
1315	add		r27=r27,carry2		};;
1316{ .mii;		getf.sig	r18=f53
1317(p6)	add		carry1=1,carry1
1318	cmp.ltu		p6,p0=r27,carry2	};;
1319{ .mfi;	st8		[r33]=r27,16
1320(p6)	add		carry1=1,carry1		}
1321
1322{ .mii;		getf.sig	r19=f44
1323		add		r17=r17,r16
1324		mov		carry2=0	};;
1325{ .mii;	getf.sig	r24=f72
1326		cmp.ltu		p7,p0=r17,r16
1327		add		r18=r18,r17	};;
1328{ .mii;	(p7)	add		carry2=1,carry2
1329		cmp.ltu		p7,p0=r18,r17
1330		add		r19=r19,r18	};;
1331{ .mii;	(p7)	add		carry2=1,carry2
1332		cmp.ltu		p7,p0=r19,r18
1333		add		r19=r19,carry1	};;
1334{ .mii;	getf.sig	r25=f63
1335	(p7)	add		carry2=1,carry2
1336		cmp.ltu		p7,p0=r19,carry1};;
1337{ .mii;		st8		[r32]=r19,16
1338	(p7)	add		carry2=1,carry2	}
1339
1340{ .mii;	getf.sig	r26=f54
1341	add		r25=r25,r24
1342	mov		carry1=0		};;
1343{ .mii;		getf.sig	r16=f73
1344	cmp.ltu		p6,p0=r25,r24
1345	add		r26=r26,r25		};;
1346{ .mii;
1347(p6)	add		carry1=1,carry1
1348	cmp.ltu		p6,p0=r26,r25
1349	add		r26=r26,carry2		};;
1350{ .mii;		getf.sig	r17=f64
1351(p6)	add		carry1=1,carry1
1352	cmp.ltu		p6,p0=r26,carry2	};;
1353{ .mii;	st8		[r33]=r26,16
1354(p6)	add		carry1=1,carry1		}
1355
1356{ .mii;	getf.sig	r24=f74
1357		add		r17=r17,r16
1358		mov		carry2=0	};;
1359{ .mii;		cmp.ltu		p7,p0=r17,r16
1360		add		r17=r17,carry1	};;
1361
1362{ .mii;	(p7)	add		carry2=1,carry2
1363		cmp.ltu		p7,p0=r17,carry1};;
1364{ .mii;		st8		[r32]=r17,16
1365	(p7)	add		carry2=1,carry2	};;
1366
1367{ .mii;	add		r24=r24,carry2		};;
1368{ .mii;	st8		[r33]=r24		}
1369
1370{ .mib;	rum		1<<5		// clear um.mfh
1371	br.ret.sptk.many	b0	};;
1372.endp	bn_mul_comba4#
1373#undef	carry2
1374#undef	carry1
1375#endif
1376
1377#if 1
1378//
1379// BN_ULONG bn_div_words(BN_ULONG h, BN_ULONG l, BN_ULONG d)
1380//
1381// In the nutshell it's a port of my MIPS III/IV implementation.
1382//
1383#define	AT	r14
1384#define	H	r16
1385#define	HH	r20
1386#define	L	r17
1387#define	D	r18
1388#define	DH	r22
1389#define	I	r21
1390
1391#if 0
1392// Some preprocessors (most notably HP-UX) appear to be allergic to
1393// macros enclosed to parenthesis [as these three were].
1394#define	cont	p16
1395#define	break	p0	// p20
1396#define	equ	p24
1397#else
1398cont=p16
1399break=p0
1400equ=p24
1401#endif
1402
1403.global	abort#
1404.global	bn_div_words#
1405.proc	bn_div_words#
1406.align	64
1407bn_div_words:
1408	.prologue
1409	.save	ar.pfs,r2
1410{ .mii;	alloc		r2=ar.pfs,3,5,0,8
1411	.save	b0,r3
1412	mov		r3=b0
1413	.save	pr,r10
1414	mov		r10=pr		};;
1415{ .mmb;	cmp.eq		p6,p0=r34,r0
1416	mov		r8=-1
1417(p6)	br.ret.spnt.many	b0	};;
1418
1419	.body
1420{ .mii;	mov		H=r32		// save h
1421	mov		ar.ec=0		// don't rotate at exit
1422	mov		pr.rot=0	}
1423{ .mii;	mov		L=r33		// save l
1424	mov		r36=r0		};;
1425
1426.L_divw_shift:	// -vv- note signed comparison
1427{ .mfi;	(p0)	cmp.lt		p16,p0=r0,r34	// d
1428	(p0)	shladd		r33=r34,1,r0	}
1429{ .mfb;	(p0)	add		r35=1,r36
1430	(p0)	nop.f		0x0
1431(p16)	br.wtop.dpnt		.L_divw_shift	};;
1432
1433{ .mii;	mov		D=r34
1434	shr.u		DH=r34,32
1435	sub		r35=64,r36		};;
1436{ .mii;	setf.sig	f7=DH
1437	shr.u		AT=H,r35
1438	mov		I=r36			};;
1439{ .mib;	cmp.ne		p6,p0=r0,AT
1440	shl		H=H,r36
1441(p6)	br.call.spnt.clr	b0=abort	};;	// overflow, die...
1442
1443{ .mfi;	fcvt.xuf.s1	f7=f7
1444	shr.u		AT=L,r35		};;
1445{ .mii;	shl		L=L,r36
1446	or		H=H,AT			};;
1447
1448{ .mii;	nop.m		0x0
1449	cmp.leu		p6,p0=D,H;;
1450(p6)	sub		H=H,D			}
1451
1452{ .mlx;	setf.sig	f14=D
1453	movl		AT=0xffffffff		};;
1454///////////////////////////////////////////////////////////
1455{ .mii;	setf.sig	f6=H
1456	shr.u		HH=H,32;;
1457	cmp.eq		p6,p7=HH,DH		};;
1458{ .mfb;
1459(p6)	setf.sig	f8=AT
1460(p7)	fcvt.xuf.s1	f6=f6
1461(p7)	br.call.sptk	b6=.L_udiv64_32_b6	};;
1462
1463{ .mfi;	getf.sig	r33=f8				// q
1464	xmpy.lu		f9=f8,f14		}
1465{ .mfi;	xmpy.hu		f10=f8,f14
1466	shrp		H=H,L,32		};;
1467
1468{ .mmi;	getf.sig	r35=f9				// tl
1469	getf.sig	r31=f10			};;	// th
1470
1471.L_divw_1st_iter:
1472{ .mii;	(p0)	add		r32=-1,r33
1473	(p0)	cmp.eq		equ,cont=HH,r31		};;
1474{ .mii;	(p0)	cmp.ltu		p8,p0=r35,D
1475	(p0)	sub		r34=r35,D
1476	(equ)	cmp.leu		break,cont=r35,H	};;
1477{ .mib;	(cont)	cmp.leu		cont,break=HH,r31
1478	(p8)	add		r31=-1,r31
1479(cont)	br.wtop.spnt		.L_divw_1st_iter	};;
1480///////////////////////////////////////////////////////////
1481{ .mii;	sub		H=H,r35
1482	shl		r8=r33,32
1483	shl		L=L,32			};;
1484///////////////////////////////////////////////////////////
1485{ .mii;	setf.sig	f6=H
1486	shr.u		HH=H,32;;
1487	cmp.eq		p6,p7=HH,DH		};;
1488{ .mfb;
1489(p6)	setf.sig	f8=AT
1490(p7)	fcvt.xuf.s1	f6=f6
1491(p7)	br.call.sptk	b6=.L_udiv64_32_b6	};;
1492
1493{ .mfi;	getf.sig	r33=f8				// q
1494	xmpy.lu		f9=f8,f14		}
1495{ .mfi;	xmpy.hu		f10=f8,f14
1496	shrp		H=H,L,32		};;
1497
1498{ .mmi;	getf.sig	r35=f9				// tl
1499	getf.sig	r31=f10			};;	// th
1500
1501.L_divw_2nd_iter:
1502{ .mii;	(p0)	add		r32=-1,r33
1503	(p0)	cmp.eq		equ,cont=HH,r31		};;
1504{ .mii;	(p0)	cmp.ltu		p8,p0=r35,D
1505	(p0)	sub		r34=r35,D
1506	(equ)	cmp.leu		break,cont=r35,H	};;
1507{ .mib;	(cont)	cmp.leu		cont,break=HH,r31
1508	(p8)	add		r31=-1,r31
1509(cont)	br.wtop.spnt		.L_divw_2nd_iter	};;
1510///////////////////////////////////////////////////////////
1511{ .mii;	sub	H=H,r35
1512	or	r8=r8,r33
1513	mov	ar.pfs=r2		};;
1514{ .mii;	shr.u	r9=H,I			// remainder if anybody wants it
1515	mov	pr=r10,0x1ffff		}
1516{ .mfb;	br.ret.sptk.many	b0	};;
1517
1518// Unsigned 64 by 32 (well, by 64 for the moment) bit integer division
1519// procedure.
1520//
1521// inputs:	f6 = (double)a, f7 = (double)b
1522// output:	f8 = (int)(a/b)
1523// clobbered:	f8,f9,f10,f11,pred
1524pred=p15
1525// One can argue that this snippet is copyrighted to Intel
1526// Corporation, as it's essentially identical to one of those
1527// found in "Divide, Square Root and Remainder" section at
1528// http://www.intel.com/software/products/opensource/libraries/num.htm.
1529// Yes, I admit that the referred code was used as template,
1530// but after I realized that there hardly is any other instruction
1531// sequence which would perform this operation. I mean I figure that
1532// any independent attempt to implement high-performance division
1533// will result in code virtually identical to the Intel code. It
1534// should be noted though that below division kernel is 1 cycle
1535// faster than Intel one (note commented splits:-), not to mention
1536// original prologue (rather lack of one) and epilogue.
1537.align	32
1538.skip	16
1539.L_udiv64_32_b6:
1540	frcpa.s1	f8,pred=f6,f7;;		// [0]  y0 = 1 / b
1541
1542(pred)	fnma.s1		f9=f7,f8,f1		// [5]  e0 = 1 - b * y0
1543(pred)	fmpy.s1		f10=f6,f8;;		// [5]  q0 = a * y0
1544(pred)	fmpy.s1		f11=f9,f9		// [10] e1 = e0 * e0
1545(pred)	fma.s1		f10=f9,f10,f10;;	// [10] q1 = q0 + e0 * q0
1546(pred)	fma.s1		f8=f9,f8,f8	//;;	// [15] y1 = y0 + e0 * y0
1547(pred)	fma.s1		f9=f11,f10,f10;;	// [15] q2 = q1 + e1 * q1
1548(pred)	fma.s1		f8=f11,f8,f8	//;;	// [20] y2 = y1 + e1 * y1
1549(pred)	fnma.s1		f10=f7,f9,f6;;		// [20] r2 = a - b * q2
1550(pred)	fma.s1		f8=f10,f8,f9;;		// [25] q3 = q2 + r2 * y2
1551
1552	fcvt.fxu.trunc.s1	f8=f8		// [30] q = trunc(q3)
1553	br.ret.sptk.many	b6;;
1554.endp	bn_div_words#
1555#endif
1556